Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: Journal of Geophysical Research: Earth Surface
Quelccaya Ice Cap is Earth’s largest tropical ice cap, and one of the most important tropical sites for paleoclimate studies. Quelccaya is located only 13 degrees south of the Equator on the Peruvian altiplano, where the high elevation of this plateau allows extensive glacier ice to survive at elevations of 5,000 meters above sea level. Glaciers and ice caps typically remove vegetation and soils from valley floors when they expand during periods of positive mass balance. However, at Quelccaya, wetland plants were buried rather than removed when the outlet glaciers advanced during the Holocene, leaving a unique archive of past variations in the ice extent.
Lamantia et al. [2023] collected rooted plant specimens for radiocarbon dating from where they had been killed in their growth positions by Quelccaya’s advancing outlet glaciers. This unusual dataset was integrated with existing samples collected over the last 20 years to give a remarkable insight into the history of tropical glaciation. Satellite imagery was used to compare this longer-term history with current changes in ice extent, indicating that the western margin of Quelccaya Ice Cap has not receded to its current position since the mid-Holocene warm period (circa. 5,000 years). This work sheds light on the magnitude and rate of current climate warming and the impact of this warming on tropical ice cover and, by extension, on regional water supplies.
Citation: Lamantia, K., Thompson, L., Davis, M., Mosley-Thompson, E., & Stahl, H. (2023). Unique collections of 14C-dated vegetation reveal Mid-Holocene fluctuations of the Quelccaya Ice Cap, Peru. Journal of Geophysical Research: Earth Surface, 128, e2023JF007297. https://doi.org/10.1029/2023JF007297
—Ann Rowan, Associate Editor, JGR: Earth Surface